Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * fixmap.h: compile-time virtual memory allocation |
| 3 | * |
| 4 | * This file is subject to the terms and conditions of the GNU General Public |
| 5 | * License. See the file "COPYING" in the main directory of this archive |
| 6 | * for more details. |
| 7 | * |
| 8 | * Copyright (C) 1998 Ingo Molnar |
| 9 | * |
| 10 | * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 |
| 11 | */ |
| 12 | |
| 13 | #ifndef _ASM_FIXMAP_H |
| 14 | #define _ASM_FIXMAP_H |
| 15 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
| 17 | /* used by vmalloc.c, vsyscall.lds.S. |
| 18 | * |
| 19 | * Leave one empty page between vmalloc'ed areas and |
| 20 | * the start of the fixmap. |
| 21 | */ |
Jeremy Fitzhardinge | 052e799 | 2006-09-25 23:32:25 -0700 | [diff] [blame] | 22 | extern unsigned long __FIXADDR_TOP; |
Jeremy Fitzhardinge | d4f7a2c | 2007-05-02 19:27:12 +0200 | [diff] [blame] | 23 | #define FIXADDR_USER_START __fix_to_virt(FIX_VDSO) |
| 24 | #define FIXADDR_USER_END __fix_to_virt(FIX_VDSO - 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | |
| 26 | #ifndef __ASSEMBLY__ |
| 27 | #include <linux/kernel.h> |
| 28 | #include <asm/acpi.h> |
| 29 | #include <asm/apicdef.h> |
| 30 | #include <asm/page.h> |
| 31 | #ifdef CONFIG_HIGHMEM |
| 32 | #include <linux/threads.h> |
| 33 | #include <asm/kmap_types.h> |
| 34 | #endif |
| 35 | |
| 36 | /* |
| 37 | * Here we define all the compile-time 'special' virtual |
| 38 | * addresses. The point is to have a constant address at |
| 39 | * compile time, but to set the physical address only |
| 40 | * in the boot process. We allocate these special addresses |
| 41 | * from the end of virtual memory (0xfffff000) backwards. |
| 42 | * Also this lets us do fail-safe vmalloc(), we |
| 43 | * can guarantee that these special addresses and |
| 44 | * vmalloc()-ed addresses never overlap. |
| 45 | * |
| 46 | * these 'compile-time allocated' memory buffers are |
| 47 | * fixed-size 4k pages. (or larger if used with an increment |
| 48 | * highger than 1) use fixmap_set(idx,phys) to associate |
| 49 | * physical memory with fixmap indices. |
| 50 | * |
| 51 | * TLB entries of such buffers will not be flushed across |
| 52 | * task switches. |
| 53 | */ |
| 54 | enum fixed_addresses { |
| 55 | FIX_HOLE, |
Ingo Molnar | e6e5494 | 2006-06-27 02:53:50 -0700 | [diff] [blame] | 56 | FIX_VDSO, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | #ifdef CONFIG_X86_LOCAL_APIC |
| 58 | FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */ |
| 59 | #endif |
| 60 | #ifdef CONFIG_X86_IO_APIC |
| 61 | FIX_IO_APIC_BASE_0, |
| 62 | FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS-1, |
| 63 | #endif |
| 64 | #ifdef CONFIG_X86_VISWS_APIC |
| 65 | FIX_CO_CPU, /* Cobalt timer */ |
| 66 | FIX_CO_APIC, /* Cobalt APIC Redirection Table */ |
| 67 | FIX_LI_PCIA, /* Lithium PCI Bridge A */ |
| 68 | FIX_LI_PCIB, /* Lithium PCI Bridge B */ |
| 69 | #endif |
| 70 | #ifdef CONFIG_X86_F00F_BUG |
| 71 | FIX_F00F_IDT, /* Virtual mapping for IDT */ |
| 72 | #endif |
| 73 | #ifdef CONFIG_X86_CYCLONE_TIMER |
| 74 | FIX_CYCLONE_TIMER, /*cyclone timer register*/ |
| 75 | #endif |
| 76 | #ifdef CONFIG_HIGHMEM |
| 77 | FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ |
| 78 | FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, |
| 79 | #endif |
Len Brown | 888ba6c | 2005-08-24 12:07:20 -0400 | [diff] [blame] | 80 | #ifdef CONFIG_ACPI |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | FIX_ACPI_BEGIN, |
| 82 | FIX_ACPI_END = FIX_ACPI_BEGIN + FIX_ACPI_PAGES - 1, |
| 83 | #endif |
| 84 | #ifdef CONFIG_PCI_MMCONFIG |
| 85 | FIX_PCIE_MCFG, |
| 86 | #endif |
Jeremy Fitzhardinge | 90caccb | 2007-05-02 19:27:13 +0200 | [diff] [blame] | 87 | #ifdef CONFIG_PARAVIRT |
| 88 | FIX_PARAVIRT_BOOTMAP, |
| 89 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | __end_of_permanent_fixed_addresses, |
| 91 | /* temporary boot-time mappings, used before ioremap() is functional */ |
| 92 | #define NR_FIX_BTMAPS 16 |
| 93 | FIX_BTMAP_END = __end_of_permanent_fixed_addresses, |
| 94 | FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS - 1, |
| 95 | FIX_WP_TEST, |
| 96 | __end_of_fixed_addresses |
| 97 | }; |
| 98 | |
| 99 | extern void __set_fixmap (enum fixed_addresses idx, |
| 100 | unsigned long phys, pgprot_t flags); |
Jeremy Fitzhardinge | 052e799 | 2006-09-25 23:32:25 -0700 | [diff] [blame] | 101 | extern void reserve_top_address(unsigned long reserve); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | |
| 103 | #define set_fixmap(idx, phys) \ |
| 104 | __set_fixmap(idx, phys, PAGE_KERNEL) |
| 105 | /* |
| 106 | * Some hardware wants to get fixmapped without caching. |
| 107 | */ |
| 108 | #define set_fixmap_nocache(idx, phys) \ |
| 109 | __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE) |
| 110 | |
| 111 | #define clear_fixmap(idx) \ |
| 112 | __set_fixmap(idx, 0, __pgprot(0)) |
| 113 | |
| 114 | #define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP) |
| 115 | |
| 116 | #define __FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) |
| 117 | #define __FIXADDR_BOOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) |
| 118 | #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE) |
| 119 | #define FIXADDR_BOOT_START (FIXADDR_TOP - __FIXADDR_BOOT_SIZE) |
| 120 | |
| 121 | #define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) |
| 122 | #define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT) |
| 123 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | extern void __this_fixmap_does_not_exist(void); |
| 125 | |
| 126 | /* |
| 127 | * 'index to address' translation. If anyone tries to use the idx |
| 128 | * directly without tranlation, we catch the bug with a NULL-deference |
| 129 | * kernel oops. Illegal ranges of incoming indices are caught too. |
| 130 | */ |
| 131 | static __always_inline unsigned long fix_to_virt(const unsigned int idx) |
| 132 | { |
| 133 | /* |
| 134 | * this branch gets completely eliminated after inlining, |
| 135 | * except when someone tries to use fixaddr indices in an |
| 136 | * illegal way. (such as mixing up address types or using |
| 137 | * out-of-range indices). |
| 138 | * |
| 139 | * If it doesn't get removed, the linker will complain |
| 140 | * loudly with a reasonably clear error message.. |
| 141 | */ |
| 142 | if (idx >= __end_of_fixed_addresses) |
| 143 | __this_fixmap_does_not_exist(); |
| 144 | |
| 145 | return __fix_to_virt(idx); |
| 146 | } |
| 147 | |
| 148 | static inline unsigned long virt_to_fix(const unsigned long vaddr) |
| 149 | { |
| 150 | BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); |
| 151 | return __virt_to_fix(vaddr); |
| 152 | } |
| 153 | |
| 154 | #endif /* !__ASSEMBLY__ */ |
| 155 | #endif |